Jul 16 2010
Evonik Industries has developed a highly transparent and weather resistant film that is based on polymethylmethacrylate (PMMA). The ROHAGLAS barrier film can be used as the front cover of solar modules, replacing the glass plates. Roll-to-roll manufacturing process is also possible with the usage of PMMA film in solar modules.
Many existing solar modules comprise crystalline solar cells, which require the semiconductor layers to be made from silicon wafers. A glass plate is needed at the front of the module to protect the cells from environmental hazards. The manufacturing of these components involves batch process, and the end product weighs nearly 20kg.
If a plastic film is used to protect the solar modules instead of glass, cost-effective solar cells can be produced. The barrier film should feature the same properties of a glass to the maximum possibility. Such properties include enabling high light transmission, and acting as a barrier to oxygen and water vapor. The plastic film should also be electrically insulating, cost-effective, UV resistant, and good adherence with solar cells.
PMMA film contains several required properties including UV stability, high transparency, and resistance to weather. In order to meet the other requirements, Evonik is developing ROHAGLAS, a multilayer film that contains several bonding and functional layers.
ROHAGLAS attains a transmission rate of 88 - 90% in the photovoltaics spectral range. The new film is being tested for compliance with the IEC 61646 standard, which involves exposing the film to UV radiation, temperature fluctuations, and other mechanical loads.
Source: http://www.acrylite.net/